CVE-2026-47737

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 82% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, Puma is vulnerable to source IP spoofing when set_remote_address proxy_protocol: :v1 is enabled and persistent connections are used because Puma incorrectly re-parses PROXY protocol headers after each keep-alive request on the same connection, allowing an attacker to inject a second PROXY header and overwrite REMOTE_ADDR. This issue is fixed in versions 7.2.1 and 8.0.2.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
18%
KEV
Not listed

Published

June 9, 2026

Last Modified

July 15, 2026

Advisory Details (7)

Auto-updated Jul 15, 2026
Patch available. Sources: github_release, github, github_commit, github_pr.
github Patch Available

Puma PROXY Protocol v1 Accepts Repeated Protocol Headers on Persistent Connections · Advisory · puma/puma · GitHub

https://github.com/puma/puma/security/advisories/GHSA-2vqw-3mp8-cgmx
github_release Patch Available

v8.0.2

Patch available: puma/puma v8.0.2

https://github.com/puma/puma/releases/tag/v8.0.2
github_release Patch Available

v7.2.1

Patch available: puma/puma v7.2.1

https://github.com/puma/puma/releases/tag/v7.2.1
github_pr Patch Available

7.2.1 backport

Patch available: puma/puma v7.2.1 (PR #3947 merged 2026-05-26)

https://github.com/puma/puma/pull/3947
github_pr Patch Available

8.0.2 backport

Patch available: puma/puma v8.0.2 (PR #3944 merged 2026-05-26)

https://github.com/puma/puma/pull/3944
github_commit Patch Available

commit ebe9db3929ab (puma/puma)

Patch available: puma/puma v7.2.1 (contains commit ebe9db3929ab)

https://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58
github_commit Patch Available

commit 439c6136d9c2 (puma/puma)

Patch available: puma/puma v8.0.2 (contains commit 439c6136d9c2)

https://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889f

Vendor Advisories for CVE-2026-47737(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
puma4.3.8-1 ... 8.0.2-3 (38 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
puma5.6.5-3 ... 8.0.2-3 (25 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
puma6.6.0-4, 8.0.2-1, 8.0.2-2, 8.0.2-3——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
puma6.6.0-48.0.2-1—
RubyGems(1)
PackageVulnerable rangeFixed inDependents
puma5.5.0 ... 7.2.0 (37 versions)7.2.1—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 49× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-25 13:49 UTCEPSS rescore
  2. 2026-08-25 00:56 UTCEG score recompute
  3. 2026-08-23 11:23 UTCEG score recompute
  4. 2026-08-23 00:19 UTCEPSS rescore
  5. 2026-08-21 23:49 UTCEPSS rescore
  6. 2026-08-21 08:19 UTCEG score recompute
  7. 2026-08-20 22:55 UTCEPSS rescore
  8. 2026-08-20 09:25 UTCEG score recompute
  9. 2026-08-19 17:04 UTCEPSS rescore
  10. 2026-08-18 13:48 UTCEPSS rescore
  11. 2026-08-17 13:47 UTCEPSS rescore
  12. 2026-08-17 01:06 UTCEG score recompute
  13. 2026-08-16 14:56 UTCEPSS rescore
  14. 2026-08-16 12:16 UTCEG score recompute
  15. 2026-08-16 02:14 UTCEPSS rescore
  16. 2026-08-15 11:39 UTCEG score recompute
  17. 2026-08-15 01:30 UTCEPSS rescore
  18. 2026-08-13 22:24 UTCEG score recompute
  19. 2026-08-13 22:00 UTCEPSS rescore
  20. 2026-08-12 23:24 UTCEG score recompute
  21. 2026-08-12 13:51 UTCEPSS rescore
  22. 2026-08-12 00:35 UTCEG score recompute
  23. 2026-08-11 01:45 UTCEG score recompute
  24. 2026-08-11 00:00 UTCEPSS rescore
  25. 2026-08-09 15:31 UTCEG score recompute
Show 42 more
  1. 2026-08-09 13:46 UTCEPSS rescore
  2. 2026-08-08 16:43 UTCEG score recompute
  3. 2026-08-08 16:37 UTCEPSS rescore
  4. 2026-08-07 17:52 UTCEG score recompute
  5. 2026-08-06 19:02 UTCEG score recompute
  6. 2026-08-06 13:47 UTCEPSS rescore
  7. 2026-08-05 20:13 UTCEG score recompute
  8. 2026-08-05 19:17 UTCEPSS rescore
  9. 2026-08-04 16:18 UTCEG score recompute
  10. 2026-08-04 15:10 UTCEPSS rescore
  11. 2026-08-04 10:39 UTCEPSS rescore
  12. 2026-08-03 15:18 UTCEG score recompute
  13. 2026-08-03 10:36 UTCEPSS rescore
  14. 2026-08-02 09:19 UTCEG score recompute
  15. 2026-08-02 02:27 UTCEPSS rescore
  16. 2026-08-01 10:29 UTCEG score recompute
  17. 2026-08-01 04:16 UTCEPSS rescore
  18. 2026-07-31 04:43 UTCEG score recompute
  19. 2026-07-30 16:28 UTCEPSS rescore
  20. 2026-07-30 11:32 UTCEG score recompute
  21. 2026-07-30 01:30 UTCEPSS rescore
  22. 2026-07-29 05:41 UTCEG score recompute
  23. 2026-07-28 15:37 UTCEPSS rescore
  24. 2026-07-28 02:49 UTCEG score recompute
  25. 2026-07-26 21:32 UTCEG score recompute
  26. 2026-07-26 14:54 UTCEPSS rescore
  27. 2026-07-25 14:18 UTCEPSS rescore
  28. 2026-07-24 14:18 UTCEPSS rescore
  29. 2026-07-23 14:18 UTCEPSS rescore
  30. 2026-07-23 03:17 UTCEG score recompute
  31. 2026-07-22 14:08 UTCEPSS rescore
  32. 2026-07-21 15:24 UTCEPSS rescore
  33. 2026-07-20 17:08 UTCEPSS rescore
  34. 2026-07-19 14:31 UTCEPSS rescore
  35. 2026-07-19 02:29 UTCEPSS rescore
  36. 2026-07-18 10:04 UTCEPSS rescore
  37. 2026-07-16 17:03 UTCEPSS rescore
  38. 2026-07-15 16:57 UTCEPSS rescore
  39. 2026-06-14 23:18 UTCEPSS rescore
  40. 2026-06-13 23:00 UTCEPSS rescore
  41. 2026-06-12 23:12 UTCEPSS rescore
  42. 2026-06-09 01:01 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-47737?
CVE-2026-47737 is a high vulnerability published on June 9, 2026. Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, Puma is vulnerable to source IP spoofing when setremoteaddress proxyprotocol: :v1 is enabled and persistent connections are used because Puma incorrectly re-parses PROXY protocol headers after each keep-alive…
When was CVE-2026-47737 disclosed?
CVE-2026-47737 was first published in the National Vulnerability Database on June 9, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-47737 actively exploited?
CVE-2026-47737 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 82.0% of all scored CVEs.
What is the CVSS score of CVE-2026-47737?
CVE-2026-47737 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-47737?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-47737, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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